1. Field of the Invention
The present invention relates to an apparatus for enclosing the exposure wire parts of coil springs protruding vertically from either an upper surface or a lower surface of a spring assembly for a bed mattress, and more particularly to an apparatus for enclosing the exposure wire parts of coil springs in a spring assembly for a bed mattress which can automate the work process according to the enclosure of the exposure wire parts, thereby maximizing work productivity.
2. Background of the Related Art
In general, a spring assembly is adapted to provide a cushion force and a buffer force through coil springs and a padding member disposed laminatedly at an upper surface or a lower surface of the coil springs. There has been proposed a protrusion-type spring assembly (hereinafter, referred to as “spring assembly”) in which at least one of the upper wire part and the lower wire part of the coil spring is vertically protrudingly disposed.
For example, as shown in FIG. 1, a spring assembly 100 includes a set of springs 110 in which coil springs 115 are arranged along row and column directions (R/C); upper and lower edge members 120 and 120′ positioned at upper and lower portions of the spring set 110, for supporting the outermost coil springs 115; and helical coil 130 engaged with the coil springs in a screw-engagement manner in the row direction of the spring set 110, for fixing corresponding wires of adjacent coil springs 115.
The coil springs 115 are vertically arranged spaced apart from one another at regular intervals between the upper and lower edge members 120 and 120′ in such a fashion as to be securely fixed at upper and lower wire parts thereof to the upper and lower edge members 120 and 120′ by means of pin members 140, respectively. Also, the coil springs 115 is formed at the upper or lower end of its housing with exposure wire parts 115a exposed upwardly or downwardly from the upper or lower edge member 120 or 120′, respectively.
Accordingly, in the case where the spring assembly 100 is embedded in a mattress (not shown) and respective padding members are stacked on the spring assembly, resilient forces of both the coil spring 115 itself and the exposure wire parts 115a are doubly exerted so as to enhance a cushion force and a buffer force, thereby improving comfort to users of the mattress.
However, the spring assembly 100 has a shortcoming in that since the exposure wire parts 115a protrude upwardly from the upper edge member 120 with respect to a horizontal plane of the spring set 110, the padding member stacked on the upper surface of the spring set 110 undesirably comes into contact with the exposure wire parts 115a while causing a damage thereto, which results in shortening the lifespan of the mattress.
In addition, the spring assembly 100 embraces demerits in that when a lateral load is applied to the exposure wire parts 115a to cause the exposure wire parts to lean to one direction, the resilient force of the coil springs is apt to be deteriorated, and in that when the leaning portion of the exposure wire part 115a comes into close contact with the upper or lower edge member 120 or 120′ or a wire part of the coil spring 115, a frictional noise may occur.
Accordingly, a technology for reducing a contact noise of the coil springs 115 has been proposed in the US. However, such a technology is merely intended to insert a pad, etc., between wire parts of the coil springs to prevent the friction noise rather than to enclose the exposure wire parts 115a. This technology still has problems in that when the leaning portion of the exposure wire part 115a comes into close contact with the upper or lower edge member 120 or 120′ or a wire part of the coil spring 115, a frictional noise may occur, and in that a dual cushion function is not sufficiently provided for a user.
In order to address and solve the above-mentioned problems, there has been proposed “an apparatus for sealing the exposure wire parts of coil springs of a spring assembly for a bed mattress” (Korean patent registration No. 444347, U.S. Pat. No. 6,983,503) by the present applicant. However, this registered patent is configured such that the exposure wire parts 115a are sealed by using a mold foam, a non-woven fabric, or the like. Therefore, the present applicant has developed an apparatus for automatically enclosing the exposure wire parts of the coil springs and has filed a patent for the apparatus.